1. Field of the Invention
The present invention relates to a shape measuring apparatus for measuring a shape of an object to be measured by irradiating the object to be measured with light and imaging the object to be measured.
2. Description of the Related Art
Conventionally, a shape measuring apparatus for measuring a surface shape of work by scanning a surface of the work by a probe and capturing position coordinates etc. of each part of the work is known.
Such a known shape measuring apparatus is a non-contact apparatus for making measurement without bringing a probe into contact with a surface of work as described in JP-T-2009-534969.
In the non-contact surface shape measuring apparatus described in JP-T-2009-534969, a surface shape of work is measured by irradiating a surface of the work with a linear line laser by a scanning probe and imaging this surface from a predetermined angle with respect to a direction of irradiation with the line laser. According to such a non-contact surface shape measuring apparatus, there is no fear of damaging the surface of the work and also considering an influence on measurement accuracy due to abrasion of the probe.
Also, an apparatus described in JP-A-2012-225700 images work using the Scheimpflug principle. By using this principle, the area of irradiation with a line laser on an imaging element changes according to a distance between a light source and the work while focus can be achieved over a wide range. Accordingly, measurement accuracy of the shape measuring apparatus decreases.